Problem 97 - Objective Biology for NEET

Question

Gibberella fujikuroi causes what disease in rice plants? (a) Foolish seeding (b) Bikaner (c) Both (a) and (b) (d) None of these

Step-by-Step Solution

Answer

The correct answer is (a) Foolish seeding.

Step 1: Identifying the organism

We first confirm that the organism in question, Gibberella fujikuroi, is a species of fungus known for causing various diseases in plants.

Step 2: Researching diseases caused by Gibberella fujikuroi

We then review or research to find out that one of the diseases that this fungus causes in rice plants is 'Foolish seeding' or 'Bakanae disease'.

Step 3: Matching the disease with the options given

We match our findings with the options given. Option (a) 'Foolish seeding' is the disease that Gibberella fujikuroi causes in rice plants. Hence, the correct answer will be (a) Foolish seeding.

Key Concepts

Gibberella fujikuroi

Gibberella fujikuroi is a species of fungus that belongs to the class Sordariomycetes. This fungus is particularly notorious in agriculture for its ability to cause diseases in various crops, prominently affecting rice plants. The fungus is adept at exploiting favorable environmental conditions to proliferate, usually thriving in warm and humid climates.

• Gibberella fujikuroi can infect seeds, seedlings, and even mature plants.
• The fungus produces spores that spread through air or water, making it difficult to control.
• It is known for causing significant reductions in crop yield, thereby impacting food security and economy.

Managing this fungus involves careful monitoring of fields, crop rotation, and the use of fungicide treatments, although resistance to treatment can sometimes occur. Understanding its life cycle and pathways of infection is critical for developing effective management strategies.

Foolish seeding disease

Foolish seeding disease, also known as Bakanae disease, is a prominent ailment in rice plants caused by the fungus Gibberella fujikuroi. This disease gets its peculiar name "foolish seeding" because it causes the rice seedlings to grow excessively tall, making them appear "foolish."

The symptoms of Foolish seeding disease include:

• Elongated stems due to overproduction of the hormone gibberellin, which the fungus produces.
• Poor root development, leading to weak plants that are easily toppled by wind or water.
• High susceptibility to breakage; the plant's structure is compromised.

The excessive growth eventually weakens the plant, reducing its ability to produce viable grains, and resulting in significant crop losses. Farmers often manage Foolish seeding disease through seed treatment with fungicides to prevent initial infection and by maintaining good field hygiene.

Rice plant diseases

Rice, being a staple food for a substantial portion of the world's population, is often subject to numerous diseases that can drastically affect yield and quality. Among these, the most notorious is the Foolish seeding disease caused by Gibberella fujikuroi. However, rice plants can fall victim to a plethora of other diseases.

Important rice diseases to be aware of include:

• Rice blast disease, caused by the fungus Magnaporthe grisea, leading to distinctive lesions on leaves and overall wilting.
• Sheath blight, a result of infection by the fungus Rhizoctonia solani, which affects the leaf sheaths.
• Bacterial blight caused by Xanthomonas oryzae, which leads to leaves turning yellow and wilting.

Each disease has its own set of management practices and treatments, often involving a combination of genetic resistance, chemical control, and agricultural practices. Effective management begins with accurate disease identification and understanding of the specific pathogen involved.